The present invention relates to radiation detection, and more particularly, to a two dimensional scintillation detector for high energy radiation like X-rays and Gamma rays.
Two dimensional solid state X-ray imaging and Gamma ray detectors are customarily fabricated by attaching a plate to, or depositing a layer of scintillating material over, the surface of an electronic imaging chip. The scintillating material, which produces low energy radiation in response to high energy radiation, is required because high energy radiation is not readily absorbed in standard semiconductor elements. Because Si chips are smaller than the finished X-ray imager, a mosaic of smaller chips needs to be assembled. It is desirable to eliminate the insensitive regions at the perimeter of and between the silicon chips where space for interconnecting wires and possible interface components could be mounted. Large prior art detectors made of a mosaic of these individual detectors have insensitive streaks where the individual Si detector arrays butt together. For example it is known from the article "Csl(Na) Scintillation Plate With High Spatial Resolution", by M. Ito et al., IEEE Trans. on Nuclear Science, Vol. NS-34, No.1, Feb. 1987, pp. 401-405, how to use multiple scintillator elements. However, light can pass between the elements resulting in cross-talk therebetween, which results in lower efficiency and blurred images.
It is therefore an object of the present invention to provide a radiation detector and method for making same with reduced dead spots and cross-talk, and also higher efficiency.